Metamorphic rocks

Formation: Sandstone with a high quartz content metamorphoses into quartzite. Extreme heat and pressure are applied to the sandstone, which causes the quartz grains to recrystallize and cement. 

Uses: Because of its strength and resilience to weathering it is used as a building material  in landscaping as an ornamental stone. When building roads, crushed quartzite is utilised.

Appearance: Generally speaking, quartzite is a thick, hard rock with a granular texture. Depending on the impurities and minerals present during the process of creating it, it can also be found in various shades of pink, red, green, and brown in addition to its usual white to grey colour.

Locations in Ireland: Ireland has deposits of quartzite in a number of counties, including Wicklow, Mayo, Galway, and Donegal. One of Galway County's most notable formations is the Connemara Mountains, where quartzite ridges are dominant.

Unusual facts: 1.Quartzite is resistant, yet it may be eroded over time by wind and water, creating interesting forms like boulders and quartzite cliffs. 

2. Numerous quartzite deposits in Ireland have been traced back hundreds of millions of years, offering important new perspectives on the area's geological past.

Formation: Marble is a metamorphic rock that is created when calcite or limestone recrystallizes in extreme heat and pressure. This process gives marble its distinctive texture by causing the minerals in the original rock to reorganise into a crystalline structure.

Uses: Marble is highly valued due of its natural beauty and adaptability. It has been a staple of design for interiors, construction, and sculpture for centuries. Common uses include wall decoration, countertops, flooring, and for ornamental purposes like sculptures and monuments.

Appearance: The seamless, glassy surface of marble usually has a variety of colours and veining characteristics. Lending to its visual appeal are contrasting colour veins that run through the stone in a variety of tones of white, grey, black, pink, green, and blue.

Locations in Ireland: Connemara Marble Quarry is a well-known source of this unusual green marble that is prized for its exquisite colouring.

Unusual facts: 1. Because Connemara Marble is one of the rarest green marbles in the world, both its aesthetic value and scarcity make it extremely desirable.

2. Several cultures utilised marble in rituals and rites because they thought it had mystical qualities.